Validate the 'License Name' value when doing the `fetch-license`

[chinyeungli]

Sometimes, user may enter the 'License Name' in the input which contradict the 'license_key'.
So, when doing the fetch-license, the tool should also validate the correctness of the 'license_name'.

[chinyeungli]

actually no validation is needed.
If user uses --fetch-license, the user should know and agree what the license name in dejacode is correct. Therefore, the license_name will be replaced with the license name from dejacode regardless what is in the input. If user doesn't want to use the Dejacode's license name for whatever reason, the user can just simply run the gen without using the fetch-license. In this case, what's in the input will be in the output.